LOUISVILLE, Ky. (AP) -- Geologists say the 4.3 magnitude earthquake that shook eastern Kentucky over the weekend was too deep to be induced by the region's underground mining activity.
The epicenter was about 10 miles west of Whitesburg, in the heart of Kentucky's coal country, where underground mining and surface blasting are common.
The head of the University of Kentucky's Geologic Hazards Section, though, says Saturday's quake occurred about 12 miles below the surface, far too deep for underground mining to have been a factor.
Zhenming Wang says it came near the Eastern Tennessee Seismic Zone. That area receives a 4-magnitude quake every five to 10 years.
Horton says mining and hydraulic fracturing -- used by the natural gas industry -- can possibly be a contributor to earthquakes but not in this case.